Quantum information processing provides a variety of new capabilities with potentially significant performance improvements over classical information processing. One example of quantum information processing is quantum computation, which can potentially solve problems that appear to be intractable using classical computers. Another application of quantum information processing is quantum cryptography that permits secure communication or exchange of keys over a distance. Yet another application of quantum information processing is quantum games, which can extend classical games such as the Prisoner's dilemma and the n-player minority game into the quantum realm to broaden the range of available game strategies.
One well-studied classical game is the public goods game, which describes social choice problems involved in provisioning for public goods. A typical example of a public goods game arises for a group deciding whether to provide a common or public good, such as a park. The well-known free rider problem arises in such classical games when the best individual result is to avoid contributing to the purchase of a public good but to free ride on the benefits of the public good purchased by others. However, if too many players are free riders, the public good is not purchased. The free rider problem arises from the individual rational decisions of players to free ride resulting in the group as a whole being worse off than if all players had contributed.
The free rider problem can be solved either by using a third party to enforce agreements or by a repeated game scenario in which participants can self-police. Government can be a good solution to the free rider problem for a public good such as national defense that involves a large population, but government may be inefficient for public goods in a smaller group such as a neighborhood. Provision of these smaller scale public goods often relies on altruism and other weaker incentives to prevent free riders. Typically, contributions to these public goods are not at efficient levels.